This is probably my favorite cool weather (<55 degrees) shirt. I recently ran a half-marathon in this shirt in cold and breezy conditions and it was great. Also, the color (bright yellow) is great if you run in neighborhoods where you have to run on streets at time and are not well lit. The shirt is very noticeable.

I tend to run early mornings or later at night, so was looking for a color that stood out. The brite orange fits the need perfectly. Other than being a tad snug in the shoulders, it fit my need for a little extra warmth during 40-50 degree runs.